class Picture < ActiveRecord::Base

validates_format_of :content_type, :with => /^image/,
:message => "--- you can only upload pictures"
def picture=(picture_field)  
  self.name = base_part_of(picture_field.original_filename)
  self.content_type = picture_field.content_type.chomp
  self.data = picture_field.read
end

def base_part_of(file_name)
name = File.basename(file_name)
name.gsub(/[^\w._-]/, '')
end

def picture
@picture = Picture.find(params[:id])
send_data(@picture.data,
:filename => @picture.name,
:type => @picture.content_type,
:disposition => "inline")
end

end
